The goal of this project is to determine the folding state of the peptide corresponding to the leucine zipper of GCN4 as a function of temperature as well as the characterization of the dynamics involved in the process. The basic strategy consists of measurements of the 1D spectra at different temperatures. The completion of the assignments is necessary for monitoring the different signals. This process is expected to be achieved by the correct elucidation of the 2D DQCOSY, TOCSY and SSNOESY spectra recorded in the same conditions. Correlation between the NMR data and thermodynamic parameters is expected to be possible in the course of this project, so the different contribution to the folding can be accessed from the NMR data. Dynamics of the peptide is followed by measuring relaxation times T1 and T2 at different conditions. Results of this type of analysis will give an information on the possible mechanism of folding of this peptide and could be used as a way to explain the protein folding mechanism of larger systems.